PIC18F2331/2431/4331/4431
REGISTER 19-2: SSPCON: SYNCHRONOUS SERIAL PORT CONTROL REGISTER
R/W-0
WCOL
R/W-0
SSPOV(1)
R/W-0
SSPEN(2)
R/W-0
CKP
R/W-0
SSPM3(3)
R/W-0
SSPM2(3)
R/W-0
SSPM1(3)
R/W-0
SSPM0(3)
bit 7
bit 0
Legend:
R = Readable bit
-n = Value at POR
W = Writable bit
‘1’ = Bit is set
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared x = Bit is unknown
bit 7
WCOL: Write Collision Detect bit
1= The SSPBUF register is written while it is still transmitting the previous word (must be cleared in
software)
0= No collision
bit 6
SSPOV: Receive Overflow Indicator bit(1)
In SPI mode:
1= A new byte is received while the SSPBUF register is still holding the previous data. In case
of overflow, the data in SSPSR is lost. Overflow can only occur in Slave mode. The user
must read the SSPBUF, even if only transmitting data, to avoid setting overflow. In
Master mode, the overflow bit is not set since each new reception (and transmission) is
initiated by writing to the SSPBUF register.
0= No overflow
In I2C™ mode:
1= A byte is received while the SSPBUF register is still holding the previous byte. SSPOV
is a “don’t care” in Transmit mode. SSPOV must be cleared in software in either mode.
0= No overflow
bit 5
SSPEN: Synchronous Serial Port Enable bit(2)
In SPI mode:
1= Enables serial port and configures SCK, SDO and SDI as serial port pins
0= Disables serial port and configures these pins as I/O port pins
In I2C mode:
1= Enables the serial port and configures the SDA and SCL pins as serial port pins
0= Disables serial port and configures these pins as I/O port pins
In both modes, when enabled, these pins must be properly configured as input or output.
bit 4
CKP: Clock Polarity Select bit
In SPI mode:
1= Idle state for clock is a high level
0= Idle state for clock is a low level
In I2C mode:
SCK release control.
1= Enables clock
0= Holds clock low (clock stretch). (Used to ensure data setup time.)
Note 1: In Master mode, the overflow bit is not set since each new reception (and transmission) is initiated by
writing to the SSPBUF register.
2: When enabled, these pins must be properly configured as inputs or outputs.
3: Bit combinations not specifically listed here are either reserved or implemented in I2C™ mode only.
2010 Microchip Technology Inc.
DS39616D-page 207
MICROCHIP [ MICROCHIP ]
